He was right. Later this year, sales of Magistri's bomb detectors will reach 1,000, including 625 for the Transportation Security Administration. The InVision Technologies machines can be found in airports all over the world with six of them in the main lobby at Portland International Airport.

Magistri, the chief executive officer of the Newark, Calif., company, helped establish InVision in 1992. Two years later it sold its first machine. By Sept. 11, 2001, InVision was one of only two companies certified to make bomb detection devices.

Sales took off, though, after 9-11, when Congress required all passenger luggage to undergo screening for explosives. InVision profits in 2002 reached $78.3 million, a tenfold increase over 2001.

Magistri, a Swiss native who holds a doctorate in biomedical engineering from the Swiss Institute of Technology in Zurich, said technology will dramatically change the look of airport security in the years ahead.

'We have by now enough technology to keep improving the system and stay ahead of the terrorists for the next 10 years,' Magistri said. 'You will see the machines finding more dangerous things and in smaller quantities.'

Screening passengers and their carry-on luggage, a process he described as a holdover from 1970s hijackings, will be different, he said.

'Possibly we'll see radar technology looking through clothes.'

Magistri also said the company will work hard to reduce the rate of false positives, which sometimes run between 20 and 30 percent. False readings have caused unnecessary airport evacuations, including one case in Sacramento, Calif., last year where an InVision machine mistook a Mickey Mouse snow globe for a bomb.

False positives also may have been an issue Sept. 8 when federal officials arrested Sheik Mohamed Abdirahman Kariye, the prayer leader of the Islamic Center of Portland, at PDX. U.S. Customs Service officials detected TNT residue in his luggage, but a subsequent test discounted the report and he was never charged with anything related to explosives.

'We still have to solve the problem of the alarm rate,' Magistri said. 'We believe we can bring it down to 1 to 3 percent, the low end of single digits.'

He sees bomb screening ultimately taking place out of sight of passengers in an online system fed automatically rather than by hand, a much faster method. But Magistri thinks there's still something to be said for operating the machines in plain sight.

'There's certainly an advantage in having the equipment out there,' he said. 'If anyone thinks to do something crazy they'll see the equipment.'